class TreeNode {
    int val;
   TreeNode left;
      TreeNode right;
      TreeNode() {}
     TreeNode(int val) { this.val = val; }
     TreeNode(int val, TreeNode left, TreeNode right) {
         this.val = val;
         this.left = left;this.right = right;}
}
public class bibtwork1 {
    
    public boolean isSameTree(TreeNode p, TreeNode q) {
        if(p==null&&q==null){
            return true;
        }
        if((p==null&&q!=null)||(p!=null&&q==null)){
            return false;
        }
        if(p.val!=q.val){//加上val比的是值 结构上交给递归
            return false;
        }
        return isSameTree(p.left,q.left)&&isSameTree(p.right,q.right);
    }
}
